A general purpose search and retrieval system includes a database or repository of source information. For example, the repository may include documents, such as books, magazines, journals, etc. In general, the user accesses the repository to retrieve selected portions of information. Computer systems have increased the use of search and retrieval systems because a computer may access a database or repository from a remote location. The utility of such a search and retrieval system is to permit a user to access one or more sources of information in a large repository. For example, a search and retrieval system may permit a user to view documents available in a large repository equivalent to a library of books.
These search and retrieval systems require ways for the user to search the information contained within the source repository to access the desired information. For example, in a document based search and retrieval system, a user searches the repository of documents to retrieve one or more documents on a selected topic. In order to narrow the selection of documents, some search and retrieval systems partition the source repository into libraries or files. If the user selects a particular library or file, then the user is permitted to access the information contained within that library or file. Typically, the libraries or files are organized into general topics. However, each library or file may still contain thousands of documents. Therefore, to locate subtopics within a more general topic, the user must search through thousands of documents.
Search and retrieval systems include a search mechanism in order to locate information in the source repository. To search for documents within the source repository, a user enters a term that most resembles the source or topic desired by the user. The proper generation of the search term is absolutely crucial to locate the most relevant documents. Typically, in such a search system, the user enters the search term, and the system displays a list of documents that contains the specific search term. If the search term is too narrow, then the user runs the risk of missing the most relevant information in the source repository. The use of a broad search term covers a wider range of topics than the narrow search term, but typically identifies too many documents. Therefore, such search systems require that the user be able to construct a search term that covers the topic adequately, without encompassing too much material. Consequently, these search systems do not provide a good way for a user to locate documents in large source repositories.
In addition to being difficult to use, search and retrieval systems are non-intuitive. A user of the system does not typically think in terms of these specific search terms that are required to produce the best search results. When a search has been conducted, a user does not know whether the search has located all the documents covering the topic desired. In addition, search and retrieval systems do not provide a user with any indication as to the classification of a document, and the location of the document within the classification structure. The retrieval of only the documents containing the specific search term leads to tunnel vision in that the user is not permitted to see other issues, known as peripheral issues, that relate to the topics desired.